Problem: If $a + b = 5$ and $x + y = -3$, what is $6b - 10x - 10y + 6a$ ?
$= 6a + 6b - 10x - 10y$ $= (6) \cdot (a + b) + (-10) \cdot (x + y)$ $= (6) \cdot (5) + (-10) \cdot (-3)$ $= 30 + 30$ $= 60$